A Bold Proposal for a Crewed Deep Space Mission to Rendezvous with and Sample an Asteroid and a Comet.

Doug Cook ahcood@yahoo.com

Geophysicist and Chair of American Association of Petroleum Geologists (AAPG) Astrogeology Committee

The technical hurdles of landing on Mars and returning are daunting compared to other crewed deep space missions. Simpler crewed deep space missions have been proposed but fail to ignite the imagination. Examples are a simple Mars fly-by and the proposed Asteroid Redirect Mission (ARM) to robotically capture a small asteroid and bring it into lunar orbit for study by crewed missions. This paper will explore a bold proposal for a crewed deep space mission using today’s technology to rendezvous with and sample an asteroid and a comet on a single mission between Earth and Mars orbit. It’s the right mission for the right time as a precursor to a Lockheed Martin crewed Mars Orbiting Lab slated for 2028 and crewed Mars landing for the mid-2030s. NASA SLS/Orion and SpaceX Falcon Heavy/Dragon crew launch vehicles with a Bigelow hab module offer the technology to get us there. Mission assembly in LEO will be necessary since no single launch vehicle could lift the deep space configuration out of Earth’s gravity well. Using JPL’s Small Body Database Search Engine, many Amor asteroid and short period comet candidates were compared with orbit and timing parameters for possible mission combinations. We propose a mission launching in 2023 to rendezvous with asteroid Bennu and comet 125P/Spacewatch on a 400 day mission. Asteroid Bennu is an Earth crossing threat with a 1/1800 chance of impacting Earth in 2182. It is a 492 meter diameter Type C carbonaceous asteroid. Asteroid Bennu is not only an opportunity for studying asteroid mining but more importantly for exploring the mysteries of extraterrestrial organics and taking steps to learn how to divert Earth crossing threats. Bennu will have been thoroughly mapped by the OSIRIS REx mission launched in September 2016. At Bennu in 2023, we propose sampling by EVA on a manned maneuvering unit (MMU). Due to outgassing, the comet sampling will need to be done with a robotic vehicle (ROV) operated by the crew at a safe distance but close enough for real time command operation. Recent robotic missions to Mars, Ceres, Pluto, and the Philae comet landing have greatly fired public imagination. This bold crewed deep space mission proposal may have the appeal to inspire international and commercial investment for funding, development, and execution.

Orbit schematic of a crewed deep space 400 day mission launching in 2023 to rendezvous with and sample asteroid Bennu and Comet 125P/Spacewatch.